Tulisa, 26, "smiled broadly" in the dock as the jury was formally discharged, reports The Guardian.

The former N-Dubz singer and X Factor judge was charged with helping to broker a drugs deal after she was targeted in a tabloid sting by Mazher Mahmood, an undercover reporter for The Sun.

Mahmood posed as a wealthy film producer, meeting Tulisa at a number of hotels and restaurants and telling her that he wanted her to star in a film alongside Leonardo DiCaprio.

He testified in court last week as a prosecution witness that Tulisa had put him in touch with her rapper friend Mike GLC, whose real name is Michael Coombs, to supply him with Class A drugs.

Tulisa denied the allegations. Her co-defendant Mike GLC, 36, previously pleaded guilty to supplying half an ounce of cocaine, which tests later showed was at 37 per cent purity, for £820.

18 July

Tulisa Contostavlos is on trial for allegedly arranging to supply cocaine to an undercover reporter who claimed he could secure her a role in a Leonardo DiCaprio film. The former N-Dubz singer and X Factor judge, who denies being involved in the deal, could face a custodial sentence if found guilty. Tulisa, allegedly helped the Sun on Sunday's undercover reporter Mazher Mahmood obtain 13.9g of a Class A drug for £860 in May last year. Her friend Michael Coombs, 36, has admitted handing over the cocaine to Mahmood on 23 May. Her lawyer insists she has joined a line of celebrities who have been used as "fodder by greedy newspapers". Here has what has happened in the trial so far...

Thursday 17 July: Simon Cowell called 'gay'

In a recording played in court, Tulisa's PA Gareth Varey was heard suggesting that media mogul Simon Cowell is gay. At a hotel last May, Varey told Mahmood he had not slept with Cowell but added: "I will when I make my move." Asked how he knew Cowell was gay, Varey replied: "I know people who have." A spokesperson for Cowell said they were not able to comment because of contempt of court rules but said they were speaking to the Attorney General's office and intend to make a statement in court as soon as possible.

Earlier in the day, Tulisa's defence lawyer accused Mahmood and his team of spiking her drink – an accusation Mahmood described as "absolutely outrageous". The defence also asked him if he had placed his hand on Tulisa's thigh in an attempt to make her feel comfortable about offering to arrange a cocaine deal for him. Mahmood replied: "No, not true."

Wednesday 16 July: Tulisa promised DiCaprio film role

Undercover reporter Mahmood posed as a rich filmmaker under the name "Samir Khan" when he met Tulisa in a Las Vegas hotel and again in a Mayfair hotel, the court has heard. Tulisa was led to believe that she was competing against Kate Winslet and Keira Knightley for a part in a Leonardo DiCaprio film, prosecutor Timothy Cray told jurors. "It is clear the defendant was very keen to break into films and she and her manager swallowed the story completely," he said.

Tulisa was "keen to be in his good books", said the prosecutor, and in a recording of a phone call she can be heard offering to help find him some "white sweets" – a codename for cocaine – for a "lads' night out". Jurors were also told that Tulisa had boasted of having an ex-boyfriend who was a major cocaine dealer, of using cannabis to get to sleep and of once being a member of a gang that sold crack cocaine. She later allegedly arranged for her friend Coombs to hand Mahmood cocaine at the Dorchester Hotel.

Tuesday 15 July: jurors warned against researching case

A jury of nine men and three women were sworn in at London's Southwark Crown Court. Judge Alistair McCreath gave them a strict warning not to research the defendant either online or by speaking to other people about the case. "She was a professional singer and she has been a judge on the X Factor. She is somebody who is famous," he said. "The upshot of that is that if you do mention this case to anybody they are bound to say something about what they think."

Monday 14 July: Tulisa suffers nose bleed on first day

Tulisa, 26, from Friern Barnet, north London, arrived in court for the first day of her trial. Proceedings were temporarily halted after she suffered a nose bleed and had to leave the court. The singer pleaded not guilty to arranging to supply a Class A drug. She appeared in the dock alongside rapper Michael Coombs, 36, of Enfield, north London, whose stage name is Mike GLC. He was bailed after pleading guilty to supplying cocaine to Mahmood and will be sentenced at the end of Tulisa's trial. He admitted to handing over the Class A drug on 23 May last year at the Dorchester Hotel in Mayfair, London.